The four themes for this month of February for Sunday Stamps hosted by Sanna @ See It On A Postcard challenge my geographical recall ... pretty exciting! The first theme is southern hemisphere. According to wiki, the entire mainland of Australia is in the southern hemisphere.
One of the iconic Australian animals is the platypus (Ornithorhynchus atatinus). On the 2016 issue above, it's shown against a background of its native foliage.
Integral to the Australian identity, too is surfing. The 2013 stamp is one of four domestic base-rate (60 cents) commemorative issued for the 50th Anniversary of Surfing Australia.
Again, according to wiki, Chinese Australians are one of the largest groups of overseas Chinese people and largest in Oceania as of 2011. For Chinese people around the world, the Lunar New Year begins on 28 January for 2017. Australia Post issued two Christmas Island Year of the Fire Rooster stamps this year. The $1 stamp is above and the other one, $3 stamp can be seen here.
Head over to Sanna's page for more stamps from the southern hemisphere.